libstdc++
gslice_array.h
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1 // The template and inlines for the -*- C++ -*- gslice_array class.
2 
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2004, 2005, 2009
4 // Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 
12 // This library is distributed in the hope that it will be useful,
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14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 
17 // Under Section 7 of GPL version 3, you are granted additional
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19 // 3.1, as published by the Free Software Foundation.
20 
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25 
26 /** @file gslice_array.h
27  * This is an internal header file, included by other library headers.
28  * You should not attempt to use it directly.
29  */
30 
31 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr>
32 
33 #ifndef _GSLICE_ARRAY_H
34 #define _GSLICE_ARRAY_H 1
35 
36 #pragma GCC system_header
37 
38 _GLIBCXX_BEGIN_NAMESPACE(std)
39 
40  /**
41  * @addtogroup numeric_arrays
42  * @{
43  */
44 
45  /**
46  * @brief Reference to multi-dimensional subset of an array.
47  *
48  * A gslice_array is a reference to the actual elements of an array
49  * specified by a gslice. The way to get a gslice_array is to call
50  * operator[](gslice) on a valarray. The returned gslice_array then
51  * permits carrying operations out on the referenced subset of elements in
52  * the original valarray. For example, operator+=(valarray) will add
53  * values to the subset of elements in the underlying valarray this
54  * gslice_array refers to.
55  *
56  * @param Tp Element type.
57  */
58  template<typename _Tp>
60  {
61  public:
62  typedef _Tp value_type;
63 
64  // _GLIBCXX_RESOLVE_LIB_DEFECTS
65  // 253. valarray helper functions are almost entirely useless
66 
67  /// Copy constructor. Both slices refer to the same underlying array.
68  gslice_array(const gslice_array&);
69 
70  /// Assignment operator. Assigns slice elements to corresponding
71  /// elements of @a a.
72  gslice_array& operator=(const gslice_array&);
73 
74  /// Assign slice elements to corresponding elements of @a v.
75  void operator=(const valarray<_Tp>&) const;
76  /// Multiply slice elements by corresponding elements of @a v.
77  void operator*=(const valarray<_Tp>&) const;
78  /// Divide slice elements by corresponding elements of @a v.
79  void operator/=(const valarray<_Tp>&) const;
80  /// Modulo slice elements by corresponding elements of @a v.
81  void operator%=(const valarray<_Tp>&) const;
82  /// Add corresponding elements of @a v to slice elements.
83  void operator+=(const valarray<_Tp>&) const;
84  /// Subtract corresponding elements of @a v from slice elements.
85  void operator-=(const valarray<_Tp>&) const;
86  /// Logical xor slice elements with corresponding elements of @a v.
87  void operator^=(const valarray<_Tp>&) const;
88  /// Logical and slice elements with corresponding elements of @a v.
89  void operator&=(const valarray<_Tp>&) const;
90  /// Logical or slice elements with corresponding elements of @a v.
91  void operator|=(const valarray<_Tp>&) const;
92  /// Left shift slice elements by corresponding elements of @a v.
93  void operator<<=(const valarray<_Tp>&) const;
94  /// Right shift slice elements by corresponding elements of @a v.
95  void operator>>=(const valarray<_Tp>&) const;
96  /// Assign all slice elements to @a t.
97  void operator=(const _Tp&) const;
98 
99  template<class _Dom>
100  void operator=(const _Expr<_Dom, _Tp>&) const;
101  template<class _Dom>
102  void operator*=(const _Expr<_Dom, _Tp>&) const;
103  template<class _Dom>
104  void operator/=(const _Expr<_Dom, _Tp>&) const;
105  template<class _Dom>
106  void operator%=(const _Expr<_Dom, _Tp>&) const;
107  template<class _Dom>
108  void operator+=(const _Expr<_Dom, _Tp>&) const;
109  template<class _Dom>
110  void operator-=(const _Expr<_Dom, _Tp>&) const;
111  template<class _Dom>
112  void operator^=(const _Expr<_Dom, _Tp>&) const;
113  template<class _Dom>
114  void operator&=(const _Expr<_Dom, _Tp>&) const;
115  template<class _Dom>
116  void operator|=(const _Expr<_Dom, _Tp>&) const;
117  template<class _Dom>
118  void operator<<=(const _Expr<_Dom, _Tp>&) const;
119  template<class _Dom>
120  void operator>>=(const _Expr<_Dom, _Tp>&) const;
121 
122  private:
123  _Array<_Tp> _M_array;
124  const valarray<size_t>& _M_index;
125 
126  friend class valarray<_Tp>;
127 
128  gslice_array(_Array<_Tp>, const valarray<size_t>&);
129 
130  // not implemented
131  gslice_array();
132  };
133 
134  template<typename _Tp>
135  inline
136  gslice_array<_Tp>::gslice_array(_Array<_Tp> __a,
137  const valarray<size_t>& __i)
138  : _M_array(__a), _M_index(__i) {}
139 
140  template<typename _Tp>
141  inline
143  : _M_array(__a._M_array), _M_index(__a._M_index) {}
144 
145  template<typename _Tp>
146  inline gslice_array<_Tp>&
148  {
149  std::__valarray_copy(_Array<_Tp>(__a._M_array),
150  _Array<size_t>(__a._M_index), _M_index.size(),
151  _M_array, _Array<size_t>(_M_index));
152  return *this;
153  }
154 
155  template<typename _Tp>
156  inline void
157  gslice_array<_Tp>::operator=(const _Tp& __t) const
158  {
159  std::__valarray_fill(_M_array, _Array<size_t>(_M_index),
160  _M_index.size(), __t);
161  }
162 
163  template<typename _Tp>
164  inline void
165  gslice_array<_Tp>::operator=(const valarray<_Tp>& __v) const
166  {
167  std::__valarray_copy(_Array<_Tp>(__v), __v.size(),
168  _M_array, _Array<size_t>(_M_index));
169  }
170 
171  template<typename _Tp>
172  template<class _Dom>
173  inline void
174  gslice_array<_Tp>::operator=(const _Expr<_Dom, _Tp>& __e) const
175  {
176  std::__valarray_copy (__e, _M_index.size(), _M_array,
177  _Array<size_t>(_M_index));
178  }
179 
180 #undef _DEFINE_VALARRAY_OPERATOR
181 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \
182  template<typename _Tp> \
183  inline void \
184  gslice_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \
185  { \
186  _Array_augmented_##_Name(_M_array, _Array<size_t>(_M_index), \
187  _Array<_Tp>(__v), __v.size()); \
188  } \
189  \
190  template<typename _Tp> \
191  template<class _Dom> \
192  inline void \
193  gslice_array<_Tp>::operator _Op##= (const _Expr<_Dom, _Tp>& __e) const\
194  { \
195  _Array_augmented_##_Name(_M_array, _Array<size_t>(_M_index), __e,\
196  _M_index.size()); \
197  }
198 
199 _DEFINE_VALARRAY_OPERATOR(*, __multiplies)
200 _DEFINE_VALARRAY_OPERATOR(/, __divides)
201 _DEFINE_VALARRAY_OPERATOR(%, __modulus)
202 _DEFINE_VALARRAY_OPERATOR(+, __plus)
203 _DEFINE_VALARRAY_OPERATOR(-, __minus)
204 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor)
205 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and)
206 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or)
207 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left)
208 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right)
209 
210 #undef _DEFINE_VALARRAY_OPERATOR
211 
212  // @} group numeric_arrays
213 
214 _GLIBCXX_END_NAMESPACE
215 
216 #endif /* _GSLICE_ARRAY_H */
ISO C++ entities toplevel namespace is std.
Reference to multi-dimensional subset of an array.
Definition: gslice_array.h:59
gslice_array & operator=(const gslice_array &)
Assignment operator. Assigns slice elements to corresponding elements of a.
Definition: gslice_array.h:147